In such electronically commutated motors (ECMs), a circuit board is used to support electronic components for controlling the motor. A so-called “window,” i.e. a hole, is provided in this circuit board, and a Hall sensor is arranged adjacent the window, in order to generate rotor position signals. This allows the motor to be compactly designed, since no additional space is needed for the Hall sensor.
In circuit boards of this kind, the problem arises that Electro-Static Discharges (ESDs) can occur during operation; these sparks or discharges can cause damage to the motor, particularly to digital electronic components used to direct motor operations.
It is therefore an object of the present invention to provide a novel electronically commutated external-rotor motor having substantially reduced vulnerability to such ESD events.